Intelligence sources claimed the organisation behind the attack is known as 'Unit 400' a secret part of the Al Quds Brigade, which falls under the direct command of Iranian Supreme Leader Ayatollah Ali Khamenei.

"Unit 400 of the Qods Force has been developing in the last few months a standing operating procedure for carrying out an attack in Turkey against western targets as well as Israeli and Jewish," Sky News quoted an intelligence source, as saying.

"It is our firm assessment that these procedures are in a very advanced stage, and that the intention is to act on the plans very soon," the source added.

According to the report, the sources revealed that there is also evidence showing Unit 400 was given instructions to carry out more frequent and more daring 'terror' attacks around the world as a demonstration of 'Iran's asymmetric power'.

The attacks were being planned in response to a growing threat of Israeli or American air strikes on its alleged nuclear weapons programme, the sources said.

The sources also named a senior officer in Unit 400 as being a key Iranian agent who 'has been working up plans for potential attacks in European countries'.

According to the report, Unit 400 is also identified as being behind the failed plot to assassinate the Saudi Ambassador to Washington using Mexican drug mafia last year. (ANI)